So, if I understand it correctly. This
shift linkage adjustment is not in the book that comes with the blower. Anyway take care and happy snowblowing. Now about that sooped up Carb of yours??
Actually, it's on page #8 of the manual. They call it, "Traction Control Linkage." It explains exactly how to install and adjust it with the gear selector in the R2 position, no doubt for an optimal adjustment. It would be the procedure if you had actually assembled the machine out of the box. That's why I didn't pay much attention to it, my mistake. The way we adjusted it seems to have also worked just fine and I see no reason to make any further adjustments.
As for the carburetor, anything you want to know, feel free to ask. I should point out to you that when it comes to removing your carburetor, the screws on the carb box, carb box hold down bracket, carb to manifold screws, and choke linkage, these were all very tight. Chances are, if you are not very careful removing them, and are not using the correct size phillips screw driver, you can actually strip them. As an example, I was very concerned about stripping the screws that hold the carburetor on the manifold. I put all my 178 lbs of body weight into them, and they wouldn't budge.
Since you can't go to a dealer for this work, I had to be a bit resourceful. So I got my wife's blow dryer, heated up the nuts to expand them. This made breaking them loose much easier. I did this same sort of thing for all the parts, heating opposite the phillips screw heads. If not for this, I would not have been able to make the carburetor switch. I lubed all the hardware before I put them back on, no way I'm going through that again. The upside to all of this was that with 2 hours on the machine since this work was done, not a hint of engine surging. The surging was what drove me over the edge to deal with this on my own. When a snowblower surges, especially in deep snow, it can't be used. If you try to work through it, you'll end up clogging the snowblower.